Transformational leadership,psychological empowerment,and the moderating role of mechanistic–organic contexts

The current study examines the empowering effects of transformational leaders and the extent to which these effects differ across mechanistic–organic organizational contexts. Psychological empowerment is hypothesized to provide a comprehensive motivational mechanism explaining the relationships between transformational leadership and employee job‐related behaviors. In addition, the relationships between transformational leadership, employee psychological empowerment, and job‐related behaviors are hypothesized to be stronger in organizations with more organic as opposed to mechanistic structures. Results based on a cross‐organizational sample of employees and their immediate supervisors provide support for the hypothesized relationships. Psychological empowerment mediated relationships between transformational leadership and employee task performance and organizational citizenship behaviors. The mediating role of psychological empowerment was then found to be conditional upon mechanistic–organic contexts. More specifically, organic structures enhanced, whereas mechanistic structures constrained, the empowering influence of transformational leaders. In highly mechanistic contexts, the indirect effects were no longer statistically significant. Implications for theory, research, and organizational management are discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

Leadership, psychological capital and safety research: Conceptual issues and future research questions

In this theory-driven literature review we examine how leadership and emerging research in positive organizational behaviour (POB) may inform our understanding of human mechanisms that affect safety outcomes. According to authentic leadership theory, leader self-awareness and self-regulation processes are vital mechanisms in the leader-follower exchange. From emerging research on authentic leadership, we propose that production management values, attitudes, and behaviour are linked to safety climate and safety outcomes in safety critical organizations (SCOs). According to recent developments in management theory, “psychological capital” is comprised of four distinct aspects that can be linked to desirable organizational outcomes and sustained high quality performance in individual workers. From this we offer a research model and five research propositions implicating that authentic leadership directly affects safety outcomes via promoting positive safety climate perceptions. Furthermore, we propose a second path where psychological capital mediates the relationship between authentic leadership, safety climate and safety outcomes in SCOs.     

Between a rock and a hard place: Accident and near-miss reporting on offshore service vessels

Reporting accidents and near misses is an important aspect of safety management. This study explores reporting in contract work, exemplified by offshore service vessels, and the associations with external and internal organisational factors. The empirical foundation for the study is a questionnaire survey (N = 1108). Reporting was negatively related to high efficiency demands from external actors and low quality of feedback to the reporting community. These factors were more strongly related to reporting than internal factors within the safety climate construct. Short-term contract engagement was also negatively associated with reporting. The results could reflect the organisational complexity that characterises much contract work. The study implies that attempts to increase the level of reporting in contract work should not be limited to focusing on internal organisational factors. Framework conditions and signals from external actors regarding the actual priority accorded to safety should also be considered.     

Response and resilience of <Emphasis Type="Italic">Spartina alterniflora</Emphasis> to sudden dieback

We measured an array of biophysical and spectral variables to evaluate the response and recovery of Spartina alterniflora to a sudden dieback event in spring and summer 2004 within a low marsh in coastal Virginia, USA. S. alterniflora is a foundation species, whose loss decreases ecosystem services and potentiates ecosystem state change. Long-term records of the potential environmental drivers of dieback such as precipitation and tidal inundation did not evidence any particular anomalies, although Hurricane Isabel in fall 2003 may have been related to dieback. Transects were established across the interface between the dieback area and apparently healthy areas of marsh. Plant condition was classified based on ground cover within transects as dieback, intermediate and healthy. Numerous characteristics of S. alterniflora culms within each condition class were assessed including biomass, morphology and spectral attributes associated with photosynthetic pigments. Plants demonstrated evidence of stress in 2004 and 2005 beyond areas of obvious dieback and resilience at a multi-year scale. Resilience of the plants was evident in recovery of ground cover and biomass largely within 3 y, although a small remnant of dieback persisted for 8 y. Culms surviving within the dieback and areas of intermediate impact had modified morphological traits and spectral response that reflected stress. These morphometric and spectral differences among plant cover condition classes serve as guidelines for monitoring of dieback initiation, effects and subsequent recovery. Although a number of environmental and biotic parameters were assessed relative to causation, the reason for this particular dieback remains largely unknown, however.     

Vegetation succession of low estuarine marshes is affected by distance to navigation channel and changes in water level

Climate change and engineering activities have modified the hydrology and morphology of estuaries. However, the potential effects of these modifications on vegetation succession in estuarine marshes are still poorly understood. Therefore, we studied temporal changes in tidal habitats of the Elbe estuary over a period of 30 years. We compared vegetation maps from 1980 to 2010 and calculated the change in area of habitats with respect to three salinity and three elevational zones. To analyze the direction of the temporal change, we differentiated between progressive and regressive succession. By using regression tree models (conditional inference trees), we identified the most influential factors determining progressive or regressive succession of low marshes. The total area of the estuarine tidal marshes at the Elbe increased by 2 % from 1980 to 2010, but changes were unequal among the salinity zones. In the salt and brackish zones, the area covered by high marshes increased substantially but decreased in the tidal freshwater zone, while that covered by low marshes decreased in all the salinity zones. Additionally, we determined high persistence of tidal flats and high marshes, whereas only 19 to 28 % of the low marshes found in 1980 remained in 2010. In salt and brackish marshes, more than two-thirds of the area that had been identified as low marshes in 1980 had progressively developed into high marshes. In contrast, 44 % of the area of low marshes in tidal freshwater marshes showed regressive succession back into tidal flats. The distance to the navigation channel was the main factor determining successional direction in salt and brackish marshes. Here, greater proximity to the channel was correlated with higher risk of regressive succession. In tidal freshwater marshes, we identified both the distance to the navigation channel and the situation on the river shore (i.e. inner bank, outer bank or straight bank) as the main factors for marsh succession. Here, considerable engineering activities in the channel had simultaneously decreased the mean low water level and increased the mean high water level between 1980 and 2010, which led to an increase in tidal amplitude. It is quite likely that these changes negatively modified marsh distribution, increased regressive succession and, thus, lowered the quality of tidal freshwater marshes.     

Functional clustering of varved lake sediment to reconstruct past seasonal climate

Annually laminated (varved) lake sediments constitutes excellent environmental archives, and have the potential to play an important role for understanding past seasonal climate with their inherent annual time resolution and within-year seasonal patterns. We propose to use functional data analysis methods to extract the relevant information with respect to climate reconstruction from the rich but complex information in the varves, including the shapes of the seasonal patterns, the varying varve thickness, and the non-linear sediment accumulation rates. In particular we analyze varved sediment from lake Kassjön in northern Sweden, covering the past 6400 years. The properties of each varve reflect to a large extent weather conditions and internal biological processes in the lake the year that the varve was deposited. Functional clustering is used to group the seasonal patterns into different types, that can be associated with different weather conditions. The seasonal patterns were described by penalized splines and clustered by the k-means algorithm, after alignment. The observed (within-year) variability in the data was used to determine the degree of smoothing for the penalized spline approximations. The resulting clusters and their time dynamics show great potential for seasonal climate interpretation, in particular for winter climate changes.     

A screening of liver,kidney, and thyroid gland morphology in organochlorine-contaminated glaucous gulls (Larus hyperboreus) from Svalbard

Concentrations of organochlorine (OC) contaminants and histomorphology of liver, kidney, and thyroid tissues were studied in nine adult and one subadult glaucous gulls (Larus hyperboreus) collected at Svalbard on 2 August 2011. Concentrations of liver polychlorinated biphenyls (PCB; range: 150–2820?ng?g^?1 ww), dichlorodiphenyltrichloroethane (DDT; range: 58–724?ng?g^?1 ww), and chlordanes (CHL; range: 11–126?ng?g^?1 ww) dominated the OC profile followed by hexachlorobenzene (HCB; range: 11–42?ng?g^?1 ww), mirex (range: 2–52?ng?g^?1 ww), and β-hexachlorocyclohexane (β-HCH; range: 1–7?ng?g^?1 ww). Histological examination of the liver showed mononuclear cell infiltrations and granulomas in 10 and 6 gulls, respectively, while intense intrahepatic lipid accumulation (steatosis) was found in two and focal necrosis in one gull. In kidney, glomerular sclerosis and adhesions was found in five and one gull, respectively. Thickening of the glomerular basement membranes and tubular necrosis was found in four and seven gulls, respectively, while mononuclear cell infiltrations were found in two individuals. In the thyroid gland, a high density of small follicles accompanied by follicular epithelial cell proliferation was observed in five glaucous gulls. Gulls with hepatic steatosis had significantly higher ΣDDT levels than the gulls without hepatic steatosis and a similar trend was found for ΣPCB. When normalizing OC concentrations for lipid content in liver, gulls with lipid granulomas had significantly lower β-HCH and significantly higher mirex levels, respectively, than gulls without lipid granulomas. Also; gulls with thickening of the glomerular basement membranes had non-significantly higher ΣPCB levels than gulls without. The histological findings were similar to those of controlled laboratory studies and OC-contaminated wildlife (e.g., polar bears; Ursus maritimus) and the data of this study therefore suggest that OC exposure may be a co-factor in the development of organ alterations in glaucous gulls. However, other environmental factors such as age, element exposure, and infectious micropathogens cannot be ruled out as co-factors, and it is uncertain if the tissue changes found exert adverse health effects on the population of Svalbard glaucous gulls.     

Chemical cocktail party in East Greenland: A first time evaluation of human organohalogen exposure from consumption of ringed seal and polar bear tissues and possible health implications

East Greenland polar bears (Ursus maritimus) are among the mammals with the highest bioaccumulated concentrations of organohalogen contaminants (OHCs). Since Greenlanders in this region ingest significant quantities of adipose tissue from polar bears and also ringed seals (Pusa hispida), initial conservative estimates of the daily oral exposure to this chemical cocktail are thus presented. The tolerable daily intake was exceeded approximately five-fold for polychlorinated biphenyls and chlordane pesticides and metabolites, while the estimated daily toxic equivalent (TEQ) (based on the 2,3,7,8-tetrachlorodibenzo-rho-dioxin toxicity equivalence factors) for East Greenland subsistence hunters was three- to ten-fold higher than the WHO ∑TEQ guidelines even though the estimations were conservative. The daily oral OHC exposure from polar bear and ringed seal blubber consumption is markedly high and needs to be reduced in order to remove this co-factor with respect to the influence on the development of chronic diseases. Furthermore, it is warranted that a physiologically based pharmacokinetic model for Greenlander's exposure to OHCs is constructed and that risk quotients calculated to estimate the threats to health for East Greenland subsistence hunters.     

Airborne fine particulate matter (PM2.5) at industrial,high- and low-density residential sites in a Nigerian megacity

Abstract

Airborne particulate matter PM_2.5 was collected in an industrial, a low-density, and a high-density residential area of Lagos from December 2010 to November 2011, and elemental composition was determined by proton-induced X-ray emission. Across the months, mass concentrations ranged from 13 to 237?µg?m^?3, exceeding the World Health Organization guideline value of 10?µg?m^?3. Data on 24 elements were obtained, with maximum values during Harmattan season months; source identification and apportionment studies by positive matrix factorization suggested that petroleum oil combustion (70%) was the major source of PM_2.5 and could pose a great hazard to Lagos receptors.